1. The Field of the Invention
This invention relates to conveyor assemblies and, more particularly, to novel systems and methods for providing an idler frame having a pivotal assembly and a selectively slidable member for exposing the rollers of the idler frame for repair or replacement.
2. The Background Art
Traditionally, materials-handling conveyor assemblies were developed by those skilled in the art for moving individual articles, such as solids, or free-flowing bulk materials (packed, unpacked or loose) over a horizontal, inclined, declined or vertical path of travel using continuous motion or movement. In particular, conveyor assemblies were designed for, but not limited to, situation in which: (1) the load to be transported was uniform and the total load was generally constant; (2) continuous movement at relatively fixed speeds was desirable; and (3) the path to be traveled was normally fixed. Correspondingly, materials-handling conveyor assemblies of the prior art typically incorporate a variety of apparatus or devices which provide mechanical movement of materials from place to place as, for example, an endless moving conveyor belt or a chain of receptacles.
Traditionally, conveyor assemblies have been used in multiple industrial applications, in warehouse and freight-handling, and in the movement of raw materials. Moreover, materials-handling machineries have been used throughout various industries in nearly every phase of production and distribution consistent with the ability to promote economy while facilitating a controlled and continuous flow of materials. In fact, many industries depend on materials-handling conveyor assemblies for their very existence.
For example, the mining industry is nearly 90% materials-handling dependent; the construction industry is roughly 90% materials-handling dependent; and, in a typical industrial manufacturing setting, approximately 50% to 75% of the overall production costs are directly related to materials-handling (an exact amount would depend upon the nature of the processes and products). In view thereof, prior art conveyor assemblies have become a symbol of industrial mass production.
Several types of conveyor assemblies have been developed by those skilled in the art to accommodate a diversity of tasks. In choosing a conveyor assembly for a particular job, primary considerations should be carefully considered, such as the characteristics of the objects(s) or materials to be handled, the distance and nature of the move to be made, and the inherent limitations or restrictions of any building or structural impediment.
One of the simplest kinds of prior art materials-handling conveyor assemblies operates using gravity or manual power (such as, chutes, roller conveyors and/or wheel conveyors, etc.) to propel objects or materials from one point to another. Other types of prior art conveyor assemblies typically use a power source and employ a belt, chain or cable to provide continuous movement. A representative group of powered prior art materials-handling conveyor assemblies may include, for example, belt conveyors, vibrating conveyors or slat conveyors.
Prior art belt conveyors consist essentially of a belt of fabric, rubber, plastic, leather or metal forming a continuous loop and supported by one or more idler frames. Customarily, prior art conveyor belt assemblies are powered by an electric motor and comprise a drive pulley which supplies motion to the conveyor belt to keep the belt moving. In design, prior art conveyor belts are generally supported by an idler frame consisting of a series of rollers or a flat slider bed to reduce friction and provide support to the conveyor belt. Conveyor belt assemblies of the prior art may also be formed having an idler frame assembly arranged so as to provide rollers which form a structural basis for a trough to facilitate maximum carrying capacity and economy of the objects or materials being moved.
Similarly, vibrating conveyor assemblies of the prior art may be designed having a trough flexibly supported by one or more idler frames which can be vibrated at a relatively high frequency and small amplitude to convey a forward motion of the bulk materials or other objects within the trough. This vibratory motion or movement typically advances the materials along the path defined by the conveyor belt. For example, one type of prior art vibrating conveyor includes an oscillating assembly which uses a relatively low frequency and a large amplitude to initiate movement of the materials on the conveyor belt.
As further characterized by the variety of powered conveyor assemblies, slat conveyor assemblies of the prior art typically consist of endless chains that are driven by electric motors which operate through reduction gears and sprockets. In addition, slat conveyor assemblies of the prior art are generally formed having spaced slats to carry objects or materials which may damage a conveyor belt because of their sharp edges or heavy weights.
In addition to the prior art conveyor assemblies outlined above, other materials-handling conveyor assemblies have been developed by those skilled in the art which utilize apparatus and devices for reciprocating jerking motions, suction and magnetic holders, forming carriers and other conventional principles and mechanisms. While conveyor assemblies of the prior art provide significant industrial advantages when moving objects or materials from place to place, several disadvantages exists when attempting to provide maintenance or repair to these assemblies.
For example, the methods and techniques used to service rollers of an idler frame of prior art materials-handling conveyors are generally underdeveloped despite the pressures from industry for labor economy and safety. In this regard, the current methods employed by those skilled in the art to mount or dismount rollers of prior art conveyor assemblies typically require two to three hours of labor and several working technicians to complete. In many instances, prior art conveyor assemblies are set high above the ground and are only partially accessible by an adjacent catwalk. To repair or replace one or more existing rollers of an idler frame, technicians must typically leave the convenience and safety of an adjacent catwalk and attempt to carefully position themselves on the side of the idler frame opposite the catwalk in order to remove the locking members disposed to retain the rollers mounted on the idler frame, thus creating the potential hazard of a technician falling from the suspended conveyor assembly.
Another disadvantage of prior art methods and techniques for mounting or dismounting rollers of an idler frame from prior art conveyor assemblies involves the possible danger of serious injury associated with having to physically lift and support the weight of a typical conveyor belt (and the objects or materials resting thereon) from its contact with the rollers of an idler frame in order to repair or replace one or more of the rollers. Corresponding to the general weight of a conveyor belt, during the lifting process, those technicians providing the labor for lifting the conveyor belt may sustain serious back injuries or other significant injuries if the bracing means supporting the conveyor belt were to give way under the force of the conveyor belt while technicians were working thereunder. Similarly, because the safety guards of prior art conveyor assembly are generally removed completely from the conveyor belt in order to service the rollers of the idler frame, an accidental start of the conveyor assembly could easily result in meaningful injuries to any or all of the technicians servicing the conveyor assembly.
Considering all these factors, the methods and techniques for servicing materials-handling conveyor assemblies of the prior art have proven to involve a substantial investment of time and labor, while creating substandard safety protocols. In accordance therewith, it would be desirable to provide an idler frame assembly for conveyors which accommodates the above-identified disadvantages.